Mary Salisbury had vital back surgery a year and six weeks after having an MRI scan and 42 weeks after seeing a consultant. Photograph: Mary Salisbury

Mary Salisbury, a retired special needs teacher, was advised to have back surgery in June 2010. But the operation did not happen until March 2011, even though NHS rules say it should have been carried out within 18 weeks.

"My back trouble began in 2009. I had an MRI scan in February 2010 at St Mary's hospital in Newport on the Isle of Wight, where I live. But I then had to wait until early June to see the consultant, as he only visits the island once a month from Southampton. He immediately recommended an operation called a laminectomy to relieve the pressure on the nerve between my fourth and fifth vertebrae, which was being crushed and causing me severe pain, a condition called a lumbar stenosis.

"The consultant said the waiting time was about 12 weeks. First, I was told the surgery should be in September or October, and then November or December. But I was never given a definite date. Every time I rang Southampton General hospital the operation receded further and further into the distance. Just before Christmas, I was told it would be 31 January, but that was cancelled. So were three subsequent operations, two of them on the day after I'd stayed in Southampton the night before and arrived as instructed at 7.30am.

"The surgery finally happened on 23 March this year – 42 weeks after I'd first seen the consultant, but a year and six weeks after I'd had the MRI scan. I've been sorted now, happily. But the wait I had to endure for treatment was inhumane and unspeakable. I was in a lot of pain, but I wasn't being treated. They said priority cases were being treated. Why wasn't I a priority? I was in serious pain and distress, couldn't sleep properly and became depressed. I'd always been a healthy person and never needed the NHS beforehand. Yet when I needed it, it wasn't there for me.

"That long wait was completely outrageous. It took a year out of my life and had a huge impact. I couldn't travel to see my children in the north of England or even go up to London to see exhibitions, which I love. I wondered: will this wait ever end?

"I should have been treated within 18 weeks: that's in the NHS constitution. But neither my doctor, the hospital or primary care trust told me that . Why not?

"I'm angry with the health secretary Andrew Lansley for saying that the 18-week treatment target wasn't effective. He airily dismissed it as unimportant and said the NHS didn't need to abide by it. In fact, 18 weeks would be absolutely fine – if they abided by it. The government must know that a lot of people are waiting way over the 18 weeks in pain and distress, like me, but they just aren't admitting it."